Blowpipe



E. FOUCHE.

BLOWPIPE.

APPLICATION FILED DEC. 21, 1919.

1,418,245. Patented y 30, 1922.

a V 29 A 2 3 EDMOND rononn, on PARIS, FRANCE.

BLOWPIPE.

neisgaes.

Specification of Letters Patent.

Patented May 30, 1922.

Application filed December 27, 1919. Serial No. 347,668.

T 0 all whom it may concern:

Be it known that I, EDMOND FoUoHri, a citizen of the French Republic andresident of 98 Avenue Niel, Paris, France, have invented certain new anduseful Improvements in Blowpipes, of which the following is aspecification. I

The oxy-acetylene blow pipes at present used for autogenous welding,generally comprise an inner oxygen jet around whlch the acetylene isadmitted, the oxygen forcing the acetylene through a mixing condult inthe body of the apparatus before leaving the outlet nozzle.

Practice hasshown that this arrangement has the drawback that on leavingthe nozzle, the mixture is richer in oxygen in the. centre than at theperiphery, owing to which a flame cannot be obtained which is neutralthroughout. The short period of contact between the two gases in themixing conduit of the apparatus is insufiicient for completely mixingthe two gases. v

The invention has for its object to remedy the above stated drawback andconsists in providing means for giving the oxygen jet an extremely thinannular formation and means for admitting the acetylene both inside andoutside of the annulus so as to produce an intimate commingling of thetwo gases in the conduit before leavingthe outlet nozzle. I

' Owing to the thinness'of the annular jet of oxygen, and to the contactof acetylene on both sides thereof, the diffusion of'the two gases isalmost'instantaneous, and the mixture escaping fromthe nozzle ispractically homogeneous throughout. conditions, the flame obtained isincapable of either carburetting or oxidizing locally, and theconsumption of oxygen is in accordance with theoretical indicationsaccording to which, with pure acetylene and oxygen, the volumes of thetwo gases simultaneously used, should be practically. equal. It isobvious that the invention can be carried out in various ways, andthat'the apparatus enabling-a thorough mixture of the two gases to beobtained by the process indicated, can be of very differentconstructions. 1 7 1 Ablow pipe according to the present invention is.shown in longitudinal, cross-section in the accompanying drawing bywayof example. v

Referring to the accompanying drawing it will be seen that the blow pipecomprises a body 1 having an outlet nozzle 2 and provided at the rearwith a breech portion 3 and a handle 4.

The breech portion 3 has a cylindrical recess or bore in which arearranged injectors constituted by two concentric tubes 5, 6, the forwardends of which are of frusto-conical form and are of such outline as toleave between them only a very narrow annular opening. These tubes areheld in spaced relation by means of rings 8 secured to the tube 5 andprovided with longitudinal grooves to enable the gas to circulate freelybetween the concentric tubes.- The tube 5' is provided at the lower partwith inlet oripressed by a nut 18 between two washers 15 and 16, theformer of which rests against the open rear end of the tube ,6, whichlatter rests in turn, with its forward conical end, against acorrespondingly shaped shoulder 17 in the front end of the breechportion,

It will'be seen that in this way the nut 18 is used not only to compressthe packing 13,

I 14 to ensure a tight joint of the ring 12; but also to force and holdthe conical end of the tube 6 against the shoulder 17 thus ensuring atight joint at this point. i In these The gases are supplied to theinjectors by the following means 2- The handle 4 is provided at its endwith nipples 19 and 20 to which are secured flexible gas supply pipes soas to connect them respectively to the pipes 21, 22; the former of thesepipes terminates in a conduit 23 which opens into the bore in the breechportion 3 opposite an orifice 24 provided in the tube 6. The

pipe 22 terminates in a conduit 25 opening into conduits 26, 27 whichlatter terminate respectively, one in a conduit 28 in the mixing chamber29, and the other in a chamber formed by the perforated ring 12.

Oxygen is admitted into the breech portion through the pipe 21 andpasses through the conduit 23. through the orifice 24 into the annularspace between the two tubes 5 and 6 and escapes through the annularnozzle 7 in the form of a thin annulus the thick ness of which can beregulated by adjusting, by means of the knob 11, the tube 5 which hasthe function of a needle valve.

The acetylene is admitted into the breech portion 8 through the pipe 22,enters the conduit 25 and divides into two currents which pass, one intothe mixing chamber 29 through the conduit 26, and the other, throughthe'conduit 27, into the admission chamber formed by the recessed ring,the latter current entering the tube 5 through the orifices 9 andescaping through the end of the said tube. I

fIt will be seen that inthis way the oxygen is discharged through theannular orifice 7 in the formiof an annulus the thickness of which canbe regulated at will and can be reduced to almostnil whilst theacetylene is admitted both internally and externally of the annulus,without the three streams of gas thus formed being permitted to mixbefore reaching the mixing chamber 29.

The gases then pass through the central conduit 30 ofthe body 1 of theblow pipe and reach the outlet nozzle 2. l

Although the foregoing description refers to a blow pipe foroxy-acetylene gas, it will be readilyunderstood that it maybe used forany other gases, for instance the oxygen couldbe replaced by atmosphericair or any othergasescapable of supporting combuss tion, and in place ofthe acetylenc,hydrogen, lightinggas, combustible vapours orliquids maybe used.

Moreover, the arrangement of the gas currents may be changed if desired,that is to say the annulus may be formed by the fuel, gasor liquid, inwhich case of course the oxidizing agent would be injected internallyand externally of the annular jet.

. Finally, in order toobtain an absolutely perfect mixture, eitherseveral similar a'nnular jets may be formed by using a larger number ofconcentric tubes,-or the annular jet could be combined with. a fullcentral jet by using three concentric tubes instead of two.

The arrangements hereinbefore described are given merely by way ofexample.-- The shapes, dimensions and details of construction may bevaried without departing from the spirit of the invention.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is 1 In a gas blowpipe, the combination with a central pipethrough which one of the gases passes, of a pipe concentric with theformer through which the other gas passes, having a COnstricted portionof conical form at the upper part of the concentric pipe to deliver thegas in the. form of an annular jet and to "form an ejector, a chamber inthe form of an enlarged pipe forming a mix ng chamber for the gases, anozzle terminating said chamber, a screw regulating device for .movingsaid central pipe axially, and means forbringing to the base of themixing chamber a jet of gas perpendicular to the annular jet. 1

2. In a gas blowpipe, a central pipe through which one of the gasespasses, a screw regulating device for moving said tube axially, a pipeconcentric with said central pipe through which the other gas passes, aconstricted conical portion at the upper part of said concentric pipe todeliver the gas in the form of an annular jet and to term an said pipe,a pipe concentric with said central pipeforthe passage of theother gas,aconical constrictedrportion at the upper part of said concentric pipe todeliver the gas in the form of an annular jet and to form an ejector,achamber in the form of an enlarged pipe receiving the annular jets ofgas and forming a mixing chamber, a nozzle terminatingsaid chamber, afirst passage emptying at the base of saidrhamber perpendicularly to theconcentric jets of gas, a

second passage, parallel with the pipes and communicating with the gaspassage to the blowpipe, a third passage parallel with the first passageand communicating with the second passage, and means placing the thirdpassage in communication with the central pipe of said ejector.

4. In I a gas blowpipe, a central pipe through which one of the gasespasses, a screw regulating device for moving-said pipe axially, a pipeconcentric with said central pipe for the passage of the other gas, aconical constricted portion at the upper part of said concentric pipe todeliver thegas in the form of an annular jet and to form an ejector, achamber in the form of an enlarged pipe receiving the annular jets andforming a mixing chamber, a nozzle terminating said chamber, a passageemptying at the base of the mixing chamber'and arranged perpendicularlyto the axis thereof, a passage perpendicular to the former and connectedto the gas intake, another passage perpendicular to thislatter andpassing to the wall of the chamber containing the ejector, a sleeve invthe itorzn'of a cupola arranged in't'he last mentioned chamber andsupporting the central pipe, the central pipe being provided withopenings for the introduction of gas, packings between the sleeve andthe corresponding ends of the exterior pipe of the ejector, and astufling box surrounding the screw regulating device of the centralpipe.

5. A gas blow pipe including a tube for furnishing an oxidizing mediumand pro vided at one end with a restricted portion,

I and provided with a bore, and means for introducing a second supply offuel into said bore at the point of meeting of the restricted portion ofthe first tube and the end of the second tube. j p

6. A blow pipe includingan outer tube provided at one end with a nozzleand having a bore provided with a restricted portion intermediate itsends, the portion of said bore on one side of the restricted portionforming a mixing chamber, a second tube mounted in the bore and having anozzle extending into said mixing chamber, means for furnishing anoxidizing medium to the interior of the second tube, a third tubearranged within the second tube and spaced therefrom to provide anannular passageway to receive the oxidizing medium, the third tubehaving one of its ends arranged at the point of the nozzle of the secondtube, and means for introducing fuel into the third tube and to saidmixing chamber at a point adjacent to the nozzle of the second tube.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

EDMOND FOUCHE. Witnesses HENBY T. WILGOIX, GEORGES BONNEUIL.

